We implement GLES3.0 instanced rendering with full support for instanced
arrays (via instance divisors). To do so, we use the new invocation
helpers to invoke a triplet of (1, vertex_count, instance_count), rather
than simply (1, vertex_count, 1). We rewrite the attribute handling code
into a new pan_instancing.c file which handles both the simple LINEAR
case for non-instanced as well as each of the new instancing cases:
MODULO (for per-vertex attributes), POT and NPOT divisors.
As a side effect, we rework how vertex buffers are handled, duplicating
them to be 1:1 with vertex descriptors to simplify instancing code paths
dramatically. This might be a performance regression, but this remains
to be seen; if so, we can always deduplicate later with some added logic
in pan_instancing.c
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
When the fault_pointer field in the header is set, we can get some idea
of which descriptor the HW isn't happy with if we know their addresses.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Arm's kernel driver mentions how to decode this field, which makes a bit
clearer what had happened.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
"Collabora, Ltd." should be listed in lieu of simply "Collabora"
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Suggested-by: Daniel Stone <daniels@collabora.com>
Identify the seamless cubemap bit and passthrough the Gallium state
rather than setting unconditionally.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
I thought I already fixed this. Maybe that was a dream...? Then again, I
might be dreaming now.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
We've known about this for a while, but it was never formally in the
machine header files / decoder, so let's add them in.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Looking at internal evidence (later fields including a literal other
compute job inception-style, seeming memory corruption, no clear
function, and the field after this being a pointer to *itself*), it
looks like this is really a much smaller descriptor.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
In OpenGL, uniforms generally represent fp32 vec4s (at least in highp
mode). In OpenCL, they represent vec2s of 64-bit pointers.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
There is fundamentally not a framebuffer associated with a compute job.
Allocate a new structure for it so we don't mess up graphics when
decoding.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
A mode for rendering tiled/uncompressed was noticed, so we reshuffle the
MFBD render target definitions to explicitly include block type.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
This combines the two cmdstream bits "is_3d" and "is_not_cubemap" into a
single 2-bit texture target selection, noticing it's the same as the
2-bit selection in Midgard and Bifrost texturing ops. Accordingly, we
share this definition and add the missing entry for 1D/buffer textures.
This requires a nontrivial (but functionally similar) refactor of all
parts of the driver to use the new definitions appropriately.
Theoretically, this should add support for buffer textures, but that's
obviously not tested and probably wouldn't work.
While doing so, we notice the sRGB enable bit, which we document and
decode as well here so we don't forget about it.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
it turns out we have explicit control over helper invocations; if a
particular bit in the fragment shader descriptor is set, helper
invocations are launched; if it clear, they are not. Helper invocations
are required whenever computing derivatives, whether explicitly
(dFdx/dFdy) *or* implicitly (any texturing). Accordingly, we set this
bit when texturing to fix edge case behaviour (literally, haha).
Thank you to Jason Ekstrand and Ilia Mirkin for pointing out the
representative dEQP test failed along triangle edges and for suggesting
helper invocations / derivatives as a list of suspect pieces (which led
to discovering the helper invocations enable bit in the first place).
Ideally we would use the new NIR analysis pass for this, but that hasn't
landed quite yet.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Following the research into Midgard's hierarchical tiling
infrastructure, we now understand (in broad stokes) the purpose of each
tiler field in the MFBD. Additionally, we understand more of the tiling
fields in the SFBD and in Bifrost's structures, although this knowledge
is still incomplete.
Update the names, decoder, and comments to reflect this new
understanding.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
These names are from the replay workaround in kbase; they begin to shine
some light on the meaning of these fields. In particular, we now
understand why the "tiler_meta" field has the effect it does on
performance in certain scenes (controlling tile granularity).
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
I don't think these are actual structures, just figments over
cargoculting dumped memory without making any sense of it. Nothing seems
to break if the region is zeroed out, anyway.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
History lesson! In the early days of a Panfrost, we had a library
independent of the driver called `panwrap` which would be LD_PRELOAD'ed
into a driver to decode its cmdstream in real-time. When upstreaming
Panfrost, we realized that we would much rather have this decode
functionality maintained in-tree to avoid divergence, but that we could
not upstream panwrap because of its use with the legacy API. So we
instead dumped GPU memory to the filesystem with an out-of-tree panwrap,
and decoded that with the in-tree pandecode module. When we migrated to
the new kernel, we just added support for doing this memory dump
directly from the driver (via a module "pantrace").
This works, but dumping memory every frame is sloooooooooooooow and
error-prone. I figured if we have pandecode in-tree, we might as well
link to it directly in the driver, allowing us to decode Panfrost's
command streams without dumping memory to the filesystem first. This
cleans up the code *substantially* and improves dumping performance by a
HUGE margin. I'm talking "several seconds per frame" to "dumping in
real-time" kind of jump.
Note to users: this removes the environmental option "PANTRACE_BASE".
Instead, for equivalent functionality set "PAN_MESA_DEBUG=trace" and
redirect stdout to the file of your choosing.
This should be debugging Panfrost much more pleasant.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
We move some coding packing the texture/sampler descriptors into
dedicated functions (out of the terrifyingly long emit_for_draw
monolith), cleaning them up as we go.
The discovery triggering the cleanup is the format for including manual
strides in the presence of mipmaps/cubemaps. Rather than placed at the
end like previously assumed, they are interleaved after each address.
This difference is relevant when handling NPOT linear mipmaps.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
The mesa/st flips the viewport, so we respect that rather than
trying to flip the framebuffer itself and ignoring the viewport and
using a messy heuristic.
However, this brings an underlying disagreement about the interpretation
of winding order to light. The blob uses a different strategy than Mesa
for handling viewport Y flipping, so the meanings of the winding order
bit are flipped for it. To keep things clean on our end, we rename to
explicitly use Gallium (rather than flipped OpenGL) conventions.
Fixes upside-down Xwayland/egl windows.
v2: Adjust lowering configuration to correctly flip gl_PointCoord.y and
gl_FragCoord.y. v1 was R-b'd by Tomeu, but then retracted due to these
regressions which are not fixed.
Suggested-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Sort-of-reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
This adds a forgotten decode line on Midgard and adds the field of a
blend constant on Bifrost. The Bifrost encoding is fairly weird; whereas
Midgard is just a regular 32-bit float, Bifrost uses a fancy
fixed-point-esque encoding. The decode logic here is experimentally
correct. The encode logic is a sort of "guesstimate", assuming that the
high byte is just int(f / 255.0) and then solving algebraicly for the
low byte. This might be slightly off in some cases.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Ryan Houdek <Sonicadvance1@gmail.com>
We already have the Bifrost disassembler in-tree, so now that panwrap is
able to dump Bifrost command streams, hook up the disassembler to
pandecode.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Ryan Houdek <Sonicadvance1@gmail.com>
With a special flag, texture descriptors can include custom stride(s).
We haven't seen a case of this used for mipmaps/cubemaps, so it's not
clear how that will be encoded, but this dumps correctly for single
one-level 2D textures.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
One field was not dumped for some reason. It's observed to be 0, but
it's still good to have it available.
Also, extra fields might be snuck in the bitmaps array (it's
variable-lengthed at the end), and we want to guard against that
possibility, so we dump a little more.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
This commit does a fairly large cleanup of blend descriptors, although
there should not be any functional changes. In particular, we split
apart the Midgard and Bifrost blend descriptors, since they are
radically different. From there, we can identify that the Midgard
descriptor as previously written was really two render targets'
descriptors stuck together. From this observation, we split the Midgard
descriptor into what a single RT actually needs. This enables us to
correctly dump blending configuration for MRT samples on Midgard. It
also allows the Midgard and Bifrost blend code to peacefully coexist,
with runtime selection rather than a #ifdef. So, as a bonus, this will
help the future Bifrost effort, eliminating one major source of
compile-time architectural divergence.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
These flags are set when reading back the tilebuffer from a fragment
shader via various mechanisms (including ARM_shader_framebuffer_fetch
and EXT_pixel_local_storage).
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
The fragment_extra structure contains additional fields extending the
MRT framebuffer descriptor, snuck in between the main framebuffer
descriptor and the render targets. Its fields include those related to
transaction elimination and depth/stencil buffers. This patch identifies
the flags field (previously just "unk" with some magic values) as well
as identifying some (but not all) flags set by the driver.
The process of identifying flags brought a bug to light where
transaction elimination (checksumming) could not be enabled unless AFBC
was in-use. This issue is now resolved.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
On MRT-capable systems, the framebuffer format is encoded as a 64-bit
word in the render target descriptor. Previously, the two 32-bit
words were exposed as opaque hex values. This commit identifies a 12-bit
Mali swizzle and a 2-bit channel counter, removing some of the magic. It
also adds decoding support for the AFBC and MSAA enable bits, which were
already known but otherwise ignored in pandecode.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
The `panwrap` utility can be LD_PRELOAD'd into a GLES app, intercepting
communication between the driver and the kernel. Modern panwrap versions
do no processing of their own; instead, they create a trace directory.
This directory contains the following files:
- control.log: a line-by-line plain text file, denoting important
syscalls (mmaps and job submits) along with their arguments
- memory_*.bin, shader_*.bin: binary dumps of mapped memory
Together, these files contain enough information to reconstruct the
command stream and shaders of (at minimum) a single frame.
The `pandecode` utility takes this directory structure as input,
reconstructing the mapped memory and using the job submit command as an
entrypoint. It then walks the descriptors as the hardware would, parsing
and pretty-printing. Its final output is the pretty-printed command
stream interleaved with the disassembled shaders, suitable for driver
debugging. For instance, the behaviour of two driver versions (one
working, one broken) can be compared by diff'ing their decoded logs.
pandecode/decode.c was originally a part of `panwrap`; it is the oldest
living code in the project. Its history is generally not worth
preserving.
panwrap itself will continue to live downstream for the foreseeable
future, as it is specifically written for the vendor kernel. It is
possible, however, to produce equivalent traces directly from Panfrost,
bypassing the intermediate wrapping layer for well-behaved drivers.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
